JP2952209B2 - How to activate a device to protect a vehicle occupant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for activating a device for protecting a vehicle occupant, and more particularly to a method for detecting vehicle acceleration along a first axis in a forward direction of the vehicle. And a second sensor for detecting the acceleration of the vehicle along a second axis that is tilted or orthogonal to the first axis, according to signals from the first and second sensors. The present invention relates to a method for activating a protection device for protecting a vehicle occupant.

[0002]

2. Description of the Related Art In a known vehicle occupant restraint system such as an inflatable air bag, when the acceleration of a vehicle measured by an accelerometer becomes equal to or more than a predetermined value indicating that the vehicle has collided, Startup is taking place. However, in the conventional sensor device, the impact is oblique (for example, 30 degrees).
If the impact is a slow step impact, the restraint is often activated considerably later. This is mainly due to the significantly different energy absorption characteristics of vehicles having parts that break in the event of frontal and oblique impacts.

Conventional devices for detecting vehicle acceleration consist of a central sensor device or a plurality of distributed sensors. However, in any case, since the acceleration signal is measured only in the longitudinal direction of the vehicle, there is a problem in activating the occupant restraint device when significant acceleration occurs along an axis other than the longitudinal direction of the vehicle. Occurs.

[0004] US-A-3851305 describes an electronic collision detection device. The apparatus is provided with a collision sensor that generates a collision signal when an object collides with a car, and a deceleration detector that generates an actual deceleration signal. Both detectors are spaced apart from each other at the front of the vehicle.

[0005]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for activating a vehicle occupant restraint device which can activate the restraint device even when the impact of the vehicle is not a forward impact. is there.

[0006]

According to the present invention, there is provided a first sensor for detecting acceleration of a vehicle along a first axis in a forward movement direction of the vehicle; A second sensor for detecting acceleration of the vehicle along a second axis inclined with respect to the axis, the method comprising: activating a protection device for protecting a vehicle occupant; In a method triggered according to a signal from a second sensor, the acceleration along a first axis sensed by the first sensor is evaluated and determined by the acceleration sensed by the first and second sensors. The overall acceleration of the vehicle is evaluated, and the protection device is activated based on the acceleration along the first axis and the overall acceleration of the vehicle.

Further, according to the present invention, a first sensor for detecting acceleration of a vehicle along a first axis in a forward moving direction of the vehicle, and a second sensor inclined along a second axis inclined with respect to the first axis. Activating a protection device for protecting an occupant of a vehicle having a second sensor for detecting acceleration of the vehicle, wherein the protection device is activated in accordance with signals from the first and second sensors. , The overall acceleration of the vehicle determined by the accelerations detected by the first and second sensors is evaluated on two channels, and the overall acceleration of the vehicle evaluated on both channels reaches a predetermined threshold value. A configuration in which the protection device is activated only when the operation is performed is adopted.

In such a configuration, the overall acceleration of the vehicle is taken into account, so that the restraint device can be reliably started even when the impact of the vehicle is not a forward impact.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Referring first to the first embodiment shown in FIG. 1, the device comprises a first sensor 10 for detecting the acceleration of the vehicle along an axis parallel to the direction of forward movement of the vehicle (hereinafter referred to as the longitudinal direction). And a sensor 12 for detecting the acceleration of the vehicle along a direction perpendicular to the longitudinal axis (hereinafter referred to as a lateral direction). The longitudinal acceleration sensor and the lateral acceleration sensor generate signals ax and ay for the evaluation means 14 and 16, respectively. The evaluation means 14 and 16 are composed of, for example, an electronic integrator and calculate the detected acceleration.

When the evaluation means 14 determines that the longitudinal acceleration is greater than a predetermined threshold, the evaluation means 14 outputs a signal b to an output stage 18 comprising a transistor switch.
Is output. The output stage is essentially an electric or electronic switch activated by the signal b, and in this embodiment the activation capsule 2 which is an inflatable restraint bag.
A signal c for starting 0 is output.

In FIG. 1, the output of the evaluation means 16 for the lateral acceleration is input to the evaluation means 14 for the longitudinal acceleration. The evaluation algorithm of the evaluation means 14 for the longitudinal acceleration is changed using the signal from the evaluation means for the lateral acceleration (for example, the speed at which the value of the acceleration is calculated is changed). Therefore, even when the detected longitudinal acceleration is not equal to or greater than the threshold value for activating the activation capsule, the evaluation means 14 determines that both the longitudinal acceleration and the lateral acceleration are activated by the signal input from the evaluation means 16. Even if not enough to activate the capsule,
It can be determined that the overall acceleration of the vehicle is sufficient to activate the activation capsule. It is also useful when the acceleration capsule in one direction is large due to the nature of the impact of the vehicle, such as an oblique impact, but the activation capsule can only be activated with a certain delay. The present invention significantly reduces such delays.

The second embodiment shown in FIG. 2 has the same components as the first embodiment shown in FIG. However, the signal ax from the vertical acceleration sensor 10 is output not only to the vertical evaluation means 14 but also to the horizontal evaluation means 16.

As before, the longitudinal acceleration is the basis for calculating whether to activate the activation capsule 20. However, the signals ax, ay from the vertical and horizontal acceleration sensors 10, 12 are processed together by the horizontal evaluation means 16. In this way, the overall magnitude and direction of the acceleration of the vehicle can be obtained, and the output of the evaluation means 16 is used to activate the longitudinal direction evaluation means 14 (for example, the activation threshold).
Can be changed. For example, even when the longitudinal acceleration ax is not sufficient and the evaluator 14 cannot activate the activation capsule 20, the evaluator 14 outputs the signal b to the output stage 18 in response to the signal from the evaluator 16, thereby outputting the signal c. The activation capsule can be activated via.

As described above, in the second embodiment, the starting capsule can be started under a predetermined condition.

In the third embodiment shown in FIG. 3, vertical and horizontal acceleration sensors 10 and 12 are provided.
Two evaluation channels, channels 1 and 2, are provided, and the outputs ax, ay from the sensors 10, 12 are input to each evaluation channel 1, 2. Channels 1 and 2 are, for example, components shown in FIG. 1 or FIG. 2 (evaluation means)
14 and 16, which perform the operations described in the first and second embodiments, respectively. Each of the channels 1 and 2 can determine whether or not the acceleration component of the vehicle has reached a predetermined threshold value independently of the other channels, and if so, each channel outputs a signal d. The output from channel 1 is input to test switch 22, while the output from channel 2 is input to output stage 18 '. This output stage 18 'has the same function as the output stage 18 of the first and second embodiments, but has four output terminals for outputting the activation signal c to each of the four activation capsules 20 shown schematically. Have. Test switch 22 is another output stage, and in a specific embodiment, output stage 1
8 'or the same as another transistor switch. The activation capsule is connected between the output stage 18 'and the test switch 22.

In this configuration, the activation capsule 20 can be activated only when receiving signals from both channels 1 and 2. Thus, even if an erroneous evaluation is made on one channel, it is protected. This is because the capsule is activated only when it is determined that the acceleration condition for activating the capsule is satisfied in both channels.

The fourth embodiment shown in FIG. 4 also has vertical and horizontal acceleration sensors 10 and 12. The acceleration signals ax and ay are input to integrators 24 and 26, respectively. The integrated signal of ax is directly input to the evaluation means 28, and it is determined whether or not the signal from the integrator 24 has exceeded a predetermined threshold. If it goes above the threshold,
That is, when the longitudinal acceleration is such that a restraining device must be used, the evaluation means 28 outputs the signal b to the output stage 3.
0 so that the activation signal c is transmitted to each activation capsule 2
0 is supplied.

The integrated signals from the integrators 24 and 26 are also supplied to a second evaluating means 32. According to the relative magnitudes of the two signals, the magnitude and direction of the acceleration of the vehicle are determined. If these are such that they exceed a predetermined threshold of the second evaluation means 32 (i.e., they are of a relative magnitude such that a collision has occurred which requires the activation of safety measures), the signal A is output and supplied to the first evaluation means 28. Thereby, as described above, the activation capsule 20
Is started.

The output signals of the integrators 24 and 26 are also input to other integrators 34 and 36, respectively.
The outputs of 4 and 36 are input to the third evaluation means 38. If the relative value of the two integrated signals exceeds a predetermined threshold value (indicating a collision in which the restraint must be activated), the evaluation means 38 outputs a signal B to output the first signal. Is input to the evaluation means 28. First evaluation means 2
8 thereby activates the activation capsule 20.

As described above, in the fourth embodiment, the activation capsule is activated when the longitudinal acceleration itself is not enough to activate, but the entire acceleration must be activated. This is most effective in cases where the longitudinal acceleration is large but the activation capsule can only be activated with a certain delay. According to this embodiment, the start-up capsule can often be started early especially when there is an oblique impact.

According to the present invention, since the sensors are arranged as a centralized unit as compared with the distributed sensors, there is an advantage that the installation cost is low and the risk of damage to the cable line is reduced. Can be The invention is also particularly suited for incorporation into existing vehicles rather than into new vehicles during manufacture.

Although the invention has been described primarily with respect to the activation of an airbag, it is of course possible to use it for other safety measures as well. For example, the signal b or c from the output stage can be used to fasten the safety belt and / or to activate the central door lock device and / or to activate the flashing warning light device or the like.

The invention also has the advantage that different functions can be performed by detecting the acceleration as a whole. For example, a central locking device and a warning flasher can be at overall sensitivity. For example, these devices can be activated when the acceleration in any direction exceeds a predetermined value, while the airbag is activated only when the forward acceleration component reaches a predetermined threshold, while belt tightening and central belt The lock can be activated with overall sensitivity according to the vehicle owner's will.

There is no need for the second sensor to detect lateral acceleration. For example, the second sensor may detect acceleration in a direction other than a direction perpendicular to the forward moving direction. For example, the sensor 12 may be configured to detect an oblique impact direction, for example, an acceleration in a direction of 30 degrees with respect to the forward movement direction.

[0026]

As described above, in the present invention, since the overall acceleration of the vehicle determined by the acceleration in the forward movement direction of the vehicle and the acceleration inclined or orthogonal to the movement direction is taken into account, the vehicle is obliquely moved. , The restraining device can be reliably started.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a device for activating an inflatable airbag according to the present invention.

FIG. 2 is a block diagram showing a second embodiment of the device for activating an inflatable airbag according to the present invention.

FIG. 3 is a block diagram showing a third embodiment of the device for activating an inflatable airbag according to the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of the device for activating an inflatable airbag according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Longitudinal acceleration sensor 12 Lateral acceleration sensor 14, 16 Evaluation means 18 Output stage 20 Activation capsule

Continued on the front page (72) Inventor Kodonnay Klaus, Federal Republic of Germany Day 6633 Vertgassen-Wadgasserstraße 65 (72) Inventor Henne Michael, Federal Republic of Germany Day 7257 (56) References JP-A-48-29125 (JP, A) JP-A-48-2646 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60R 21/32

Claims (5)

(57) [Claims] A first sensor for detecting acceleration of the vehicle along a first axis in a forward movement direction of the vehicle;
And a second sensor (12) for detecting acceleration of the vehicle along a second axis inclined with respect to the first axis, the method comprising activating a protection device for protecting a vehicle occupant. And estimating the acceleration along a first axis sensed by the first sensor, wherein the protection device is activated according to signals from first and second sensors. Evaluating the overall acceleration of the vehicle determined by the acceleration detected by the sensor, and activating the protection device based on the acceleration along the first axis and the overall acceleration of the vehicle. To activate equipment to protect people. 2. A first sensor for detecting acceleration of a vehicle along a first axis in a forward movement direction of the vehicle.
And a second sensor (12) for detecting acceleration of the vehicle along a second axis inclined with respect to the first axis, the method comprising activating a protection device for protecting a vehicle occupant. And wherein the protection device is activated in accordance with signals from first and second sensors, wherein the overall acceleration of the vehicle determined by the acceleration detected by the first and second sensors is evaluated in two channels. A method for activating a device for protecting a vehicle occupant, wherein the device is activated only when the overall acceleration of the vehicle evaluated in both channels reaches a predetermined threshold value. 3. The first and second sensors (10, 12).
3. The method according to claim 1, wherein the sensors are arranged to detect accelerations in two directions orthogonal to each other. 4. The first and second sensors (10, 12).
4. The method according to claim 1, wherein is located centrally. 5. The method according to claim 4, wherein said first and second sensors are located in a housing.